Strength of Epoxy Adhesives when Stressed to Failure in Milliseconds

The data presented demonstrate that the adhesives tested exhibit a greater resistance to rapidly applied or dynamic loads than they do to loads applied at static rates. The difference observed between the dynamic and static strengths is dependent upon the formulation of the particular adhesive. At low temperatures where the molecular motion is greatly restricted, the bond strengths obtained do not as a rule vary much with rate of load. However, as the test temperature increases, the molecular motion increases, and unless some factor is present that will restrict this movement the resistance to applied loads becomes more time dependent.